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S-meter readings when using an Airspy HF+
Patrick
Hi there, Last night, I made a recording on MW, using a my HF+ with its default settings (HF AGC ON, HF Threshold LOW, HF Preamp unticked) and SDR# latest version / firmware. Antenna is a Wellbrook ALA1530LN mounted outdoors. Listening to the files right now on v3 (to run your amazing Data File Analyser), I notice the S-meter readings are very high and seem "overrated". AM mode, 4 kHz filter reads -60 dBm on a "clear" frequency, and about -20 dBm on powerful stations. Using AGC OFF with Gain set 0 dB even causes distorision. When recording from an ELAD S2, the loudest stations read about -50 dBm. Similar values if recording with an RSPduo and playing back with SDRuno software. That's about 30dB discrepancy. Should I modify some settings on my HF+ before recording ? What does explain such a hugh difference between both SDRs ? (note : a couple of months ago, I recorded from v3 but then it was impossible to use the file with SDR#, I mean the waterfall was totally saturated, no way to see a single signal even with contrast at its lowest). Thanks for tips / suggestions BR.
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paul newcombe <G6YZC@...>
BR,
I love SDRC but think it should come with a bottle of Typex (White out) and the first thing you should do is cover up the S meter.
When ever most people I have spoken with try to use SDRC and an SDR they immediately add as much attenuation in front of it as needed in order to make the S Meter read the same as their big 3 brick rig. The next thing they do is complain that the SDR is deaf
and totally useless.
I know on 2m EME my SDRC S meter reads somewhere around -71 dBm (off the top of my head) and I also know with a -71dBm noise floor you cannot do EME. So I just ignore the meter and continue to work stations off the moon.
Paul N2EME
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> on behalf of Patrick <aunumero73@...>
Sent: Wednesday, September 26, 2018 7:57 AM To: main@sdr-radio.groups.io Subject: [SDR-Radio] S-meter readings when using an Airspy HF+ Hi there,
Last night, I made a recording on MW, using a my HF+ with its default settings (HF AGC ON, HF Threshold LOW, HF Preamp unticked) and SDR# latest version / firmware. Antenna is a Wellbrook ALA1530LN mounted outdoors.
Listening to the files right now on v3 (to run your amazing Data File Analyser), I notice the S-meter readings are very high and seem "overrated".
AM mode, 4 kHz filter reads -60 dBm on a "clear" frequency, and about -20 dBm on powerful stations.
Using AGC OFF with Gain set 0 dB even causes distorision.
When recording from an ELAD S2,
the loudest stations read about -50 dBm. Similar values if recording with an RSPduo and playing back with SDRuno software.
That's about 30dB discrepancy.
Should I modify some settings on my HF+ before recording ?
What does explain such a hugh difference between both SDRs ?
(note : a couple of months ago, I recorded from v3 but then it was impossible to use the file with SDR#, I mean the waterfall was totally saturated, no way to see a single signal even with contrast at its lowest).
Thanks for tips / suggestions
BR.
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Patrick
EDIT : of course, when I wrote : "
Should I modify some settings on my HF+ before recording ?" I was refering to the setting from SDR# "source" window (HF AGC, HF treshold, HF preamp, HF att)
Le mer. 26 sept. 2018 à 13:57, Patrick <aunumero73@...> a écrit :
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Bjarne Mjelde
Be aware that the standard signal level readings in SDR# is not dBm but dBFS.
-- Bjarne Mjelde arcticdx.blogspot.com Remote rx: kongsdr.proxy.kiwisdr.com:8073/
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